Speaking of schematic review, post the schematics of everything from the battery up to where it connects to the overo.  I just finished a project using the 18650 batteries and its going just fine.  But then again, I'm only using 1 battery and a boost mode supply.

From: Paul Nolan <idrunapersonal@gmail.com>
To: General mailing list for gumstix users. <gumstix-users@lists.sourceforge.net>
Sent: Friday, October 21, 2011 5:44 AM
Subject: Re: [Gumstix-users] How have I managed to kill 10 Overos?

On Wed, Oct 19, 2011 at 5:01 PM, William Pretty Security Inc <bill.pretty@xplornet.com> wrote:
Also I know it sounds trite, but why don't you use a battery and a linear
regulator ?
I know it's a pain in the ass, but it's a lot cheaper that 10 Overo's :-(


Make that 11.  I`m testing a linear regulator now, but it gets too hot to use for more than a short time (system is powered by two 18650 batteries in series, so 7.2-8.4V).   My other test was to add a super cap to the 3.3V switching regulator.  Worked fine for over 100 battery insertions.  The next day I inserted the battery and the Overo died, to the sound of much cursing.  I`ve tested the voltage on an oscilloscope, and the voltage goes up in a straight line with no overshoot when the battery is inserted.  The TPS chip on the Overo is supposed to be able to handle up to  4.2V and spikes up to 5.2V, so I have no idea what can be causing my problems.

If I don't' have a solution by Monday I`ll have no choice but to switch to a COM supplier that offers technical support such as schematic review services etc.  

The demand for IT networking professionals continues to grow, and the
demand for specialized networking skills is growing even more rapidly.
Take a complimentary Learning@Cisco Self-Assessment and learn
about Cisco certifications, training, and career opportunities.
gumstix-users mailing list